Port 43 is used for WHOIS queries. WHOIS is a protocol used to query databases that store information about domain name registrations and IP addresses. When port 43 is used to send a query to a WHOIS server, the server responds with information about the queried domain name or IP address. This information often includes the name and contact information of the domain name registrant, as well as the domain name registrar, the creation and expiration dates of the domain name registration, and the nameservers associated with the domain name.
Ports those registered with IANA are shown as official ports. The same port number may be unofficialy used by various services or applications. The official usage are listed separately below its usage may change from time to time.
Official
Port |
Protocol (TCP/UDP) |
Title |
Description |
Port Type |
Port 43 |
tcp |
nicname |
Who Is |
WELL KNOWN PORT |
Port 43 |
udp |
nicname |
Who Is |
WELL KNOWN PORT |
UnOfficial
Unofficialy or sometimes with conflict, the same port may be used by different applications.
| Port | Protocol (TCP/UDP) | Description |